configureServer.scala

def configureServer(serverNames: ServerNames): () => Unit = {
  // Recreate data directory
  if (dataDir == null || dataDir == "") {
    dataDir = "./zookeeper-" + nodeId
  }
  val dir = new File(dataDir)
  log.info("(Re)creating data directory: " + dataDir)
  rmdir(dir)
  dir.mkdirs()

  val startupProperties = new Properties()
  
  if (serverNames.useReplicated) {
    for ((server, idx) <- serverNames.hosts.zipWithIndex) {
      startupProperties.put(serverNames.serversKey(idx), serverNames.serversVal(idx))

      // Create myid file
      if (server == nodeId) {
        val myidFile = new File(dir, "myid")
        val fw = new FileWriter(myidFile)
        fw.write((idx+1).toString + "\n")
        fw.close()
      }
    }
  }

  startupProperties.put("tickTime", "1000")
  startupProperties.put("initLimit", "10")
  startupProperties.put("syncLimit", "5")
  startupProperties.put("dataDir", dataDir)
  startupProperties.put("clientPort", clientPort.toString)
  startupProperties.put("skipACL", "true")
  startupProperties.put("autopurge.purgeInterval", "24")
  
  val (serverStartFunc, server) =
    if (serverNames.useReplicated) {  // Replicated Zookeeper
      val quorumConfiguration = new QuorumPeerConfig
      quorumConfiguration.parseProperties(startupProperties)
      val quorumPeerMain = new QuorumPeerMain

      val startFunc = { () =>
        quorumPeerMain.runFromConfig(quorumConfiguration)
      }
      (startFunc, quorumPeerMain)

    } else {  // Standalone Zookeeper
      val quorumConfiguration = new QuorumPeerConfig
      quorumConfiguration.parseProperties(startupProperties)
      val configuration = new ServerConfig
      configuration.readFrom(quorumConfiguration)
      val zkServerMain = new ZooKeeperServerMain

      val startFunc = { () =>
        zkServerMain.runFromConfig(configuration)
      }
      (startFunc, zkServerMain)
    }
    
  zkServer = Some(server)
  serverStartFunc
}